The ectodermal dysplasias are a heterogeneous group of heritable disorders characterized by abnormalities of the embryonic ectoderm. Controversy exists over which syndromes should be classified as ectodermal dysplasias and which should be excluded from the classification. Freire-Maia (1971) offered the first clinical classification of ectodermal dysplasias. He based his classification on the observed clinical phenotype affecting mainly the hair, teeth, sweat pores and nails. According to this classification there are over 170 conditions that could be considered ectodermal dysplasias. With the rapid advance of the study of the human genome, new approaches for classifications for ectodermal dysplasias have been proposed. Indeed Priolo M. (2000) proposed a classification integrating molecular genetics and clinical aspects. However, Priolo's classification as well as that of Freire-Maia has the difficulty that when applied strictly several additional groups of diseases should be integrated to the term ectodermal dysplasias. Lamartine J. (2003) has proposed a classification based on causative genes function. This classification considered four subgroups: cell-cell communication and signaling; adhesion; transcription regulations; and development. The study of the human genome has accelerated the knowledge in cell function making this time very appropriate to host an international conference of experts to update transfer and disseminate a new classification for ectodermal dysplasias. The conference proposal aims to analyze, discuss present classifications of ectodermal dysplasia and to generate consensus to develop a modern classification considering the recent advances in molecular genetics. The significance of the conference results are two folds, a new classification will foster a better understanding of ectodermal dysplasias and will open new field of research. [unreadable] [unreadable] [unreadable]